CERAMICS INTERNATIONAL
·
2022
·
IF 5.532
Yan Ziyang,Wu Angxuan,Wang Xilin,Huang Rongxia,Yan Nianping,Jia Zhidong,Wang Liming
In this paper, ZnO was used as a sintering aid as well as reactant in the reactive flash sintering (RFS) of zinc-containing ceramic materials at room temperature (25 °C). The RFS of ZnO-based ceramics, both ZnAl 2 O 4 and Zn 2 TiO 4 , were achieved with the application of a high electric field. Contrary to previous reports, the RFS of ZnAl 2 O 4 was divided into two stages according to temperature changes, and the effect of the reaction exotherm on the RFS was presented for the first time in this paper. In addition, the RFS produced a larger grain size of ZnAl 2 O 4 than conventional sintering did.
研究领域:
材料科学
·
陶瓷工程
✓ 已验证
DOI
高影响因子
FUEL
·
2024
·
IF 6.7
Jian Li,Wen Fu,Xiaowei Bai,Xiangrui Lin,Heping Yang,Mengfei Wang,Guangxuan Liu,Zhenghua Dai
Oxidative pyrolysis of biomass, which introduces controlled oxygen into the reaction, enables autothermal processes and addresses heat transfer challenges in large reactors. Oxygen promotes exothermic reactions and changes product composition. Given the unique chemistry of cellulose, hemicellulose, and lignin, their pyrolytic behaviors vary with oxygen levels. This study examines these variations. The results indicate that when 10 vol% of oxygen is introduced, for cellulose, the main impact is on the third (310–410 °C) and fourth (410–700 °C) stages of pyrolysis, where O 2 reacts with the produced sugars (reducing by 6.6 %) and biochar to generate CO, a small amount of CO 2 , and water; for hemicellulose, the main impact is on the fourth stage (340–850 °C), where O 2 reacts with the produced biochar to generate CO, a small amount of CO 2 , and water; for lignin, the main impact is on the second (190–410 °C) and third (410–850 °C) stages, where O 2 reacts with the produced phenolic monomers (reducing by 2.2 %) and biochar to generate CO 2 , a small amount of CO, and water. Cellulose and hemicellulose generate more CO in oxidative pyrolysis, whereas lignin produces more CO 2 , due to varying oxygen content. Furthermore, after the introduction of 10 vol% of oxygen, the pyrolysis process of both lignin and cellulose is advanced, with lignin reaching an exothermic peak value of 18.6 mW/mg, which is 5.3 mW/mg higher than that of cellulose and 11.2 mW/mg higher than that of hemicellulose, indicating that lignin releases the most heat, while hemicellulose releases the least.
研究领域:
能源与环境科学
·
生物质化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2022
·
IF 6.371
Xiaogang Guo,Taotao Liang,A. Segun Giwa
Development of the structural, anti-wetting and exothermic stability of composite metal based-energetic composite is still a great challenge, especially used in complex environments (e.g. moisture circumstances). Thus, this paper firstly proposed electrophoretic controlled assembly (ECA) technique and facile modification process to construct the multifunctional nano-Al based NiO/perfluorosilane energetic composite films with even distribution of nanoscale particles and triple (a: microstructure, b: anti-wetting and c: exothermic performance) stability of for three years. The ECA dynamics study of Al/NiO particles was deeply explored as a “controlled bridge” to adjusting the reaction ratio of Al to NiO in product. The target film displays an outstanding high water contact angle of 171 ± 1° with an almost perfect sphere of droplet placed on that surface, and shows a small fluctuation of anti-wetting ability after immersed and exposure tests. In addition, the total heat output (Q) of product can reach up to ~2.5 kJ/g with a low activation energy of 247.624 kJ/mol, and shows ultra-long exothermic stability for three years. The realization of target film highly compatible with microelectromechanical systems (MEMS) here will largely improve the safety level of propellant or detonator system.
研究领域:
材料科学
·
能源化学
✓ 已验证
产品关联
DOI
高影响因子
POLYMERS FOR ADVANCED TECHNOLOGIES
·
2023
·Vol. 35
·期 1
·e6238
·
IF 3.4
Ben Hu,Jun Wang,Xi Chen,Jingsheng Wang,Shuang Yang,Lu Zhu,Lanian Zou,Siqi Huo
This work reported a flame-retardant, single-component epoxy resin (EP) via introducing diphenylphosphine (DPP) and benzimidazolyl-substituted cyclotriphosphazene (BICP) into EP. The differential scanning calorimetry (DSC) test showed that the onset curing temperature of DPP/BICP-15/10 was 50°C lower than that of BICP-12 due to the catalytic decomposition effect of DPP toward BICP under heating. Besides, the shelf life of DPP/BICP-15/10 at room temperature reached ~14 days, demonstrating good storage stability. EP/DPP/BICP maintained satisfactory thermal properties and showed excellent flame retardancy with a UL-94V-0 classification. Compared with the unmodified EP sample, the peak heat release rate (PHRR) and total heat release (THR) of DPP/BICP-15/13 were decreased by ~68.1% and ~55.1%, respectively. Hence, this flame-retardant, single-component epoxy resin with satisfactory comprehensive properties exhibited great potential for versatile industrial applications.
研究领域:
材料科学
·
化学工程
·
高分子科学
✓ 已验证
DOI
高影响因子
International Journal of Electrochemical Science
·
2023
·
IF 1.5
Miao He,Yuting Xie,Zihui Ni,Xuzhong Zeng,Hebin Bao,Xiaodi Wu,Li Liu,Xueming Li,Qihui Wang
Based on the superior exothermic properties, Al/CuO nanothermites are considered as one of the most promising energetic materials in recent years. In this work, the CuO nanospheres with particle size of 100–120 nm were successfully synthesized by a simple solution route and subsequent heat treatment, and used as oxidizer of Al/CuO nanothermites. The electrophoretic deposition kinetics of Al/CuO nanothermites were investigated in detail. Then, the morphology and composition of the as–prepared Al/CuO nanothermites were characterized by means of scanning electron microscopy (SEM), X–ray diffraction (XRD), X–ray photoelectron spectroscopy (XPS), and spectrophotometry. The results show that the electrophoretic deposition behavior of Al/CuO nanothermites is controlled by diffusion. Furthermore, there is a linear relationship between the equivalent ratio in the suspension (Ф d ) and the deposited film (Ф s ). The Ф d can be precisely adjusted by changing the electrophoresis parameters. When the equivalent ratio of Al/CuO nanothermites in the suspension is 1.5, the heat release of the sample can reach up to 1977 J/g. This work provides a new strategy for the preparation of nanothermites by electrophoretic deposition.
研究领域:
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
International Journal of Smart and Nano Materials
·
2022
·
IF 4
Junjie Wei,Long Li,Rui Li,Qingquan Liu,Zejun Yan,Tao Chen
Smart hydrogel with color responsiveness is envisioned as one of the most promising materials for advanced information encryption and decryption platform, but the illumination-dependent way of decrypting and reading information leads to the worrying of concealment in some particular scenarios. Herein, we proposed a smart hydrogel information platform with dual imaging modes by utilizing the accompanying behaviors in transparency change and heat releasing after crystallization of supercooled solution. For this smart hydrogel information platform, the hidden information could be written and decrypted by ink of ethylene glycol and decryption tool of seed crystal, respectively. Furthermore, in addition to the traditional optical imaging mode with the assistance of light illumination, the decrypted information on dual-imaging-mode hydrogel platform also could be read by thermal imaging mode in dark environment owing to the exothermic crystallization. The illumination-independent read mode based on heat radiation helps to improve the secrecy and safety of the decryption and read process. This investigation provides a facile and feasible strategy to design illumination-independent information platform that enables reading the encrypted information in secret.
研究领域:
材料科学
·
信息学
·
化学
✓ 已验证
产品关联
DOI
高影响因子
Materials Research Express
·
2021
·Vol. 8
·期 3
·035501
·
IF 1.62
Chao Li,Guodong Zeng,Min Zhou,Yang Fang,Zongwu Chen,Yishen Xu,Siyin Ding,Miao Yuan,Hao Li,Shaopeng Wu
Combination of styrene-butadiene-styrene (SBS) polymer and layered double hydroxides (LDHs) has commonly applied in asphalt to improve anti-ultraviolet aging performance, but it can not afford the reparation of cracks caused by aging of asphalt. Also, few researches focused on the structure and performance changes during synthesis of LDHs. Based on self-healing performance of asphalt, the produced cracks can be repaired by microwave heating. Therefore, the controllable synthesis of traditional microwave absorber SiC to wrap LDHs (SwL) at different temperatures was studied in this paper, and the effects of different SBS/SwL combination on the microwave absorption and exothermic properties of modified asphalt were studied. The SwL was firstly synthesized at 200 °C, 350 °C, 500 °C and 650 °C. Then morphology, phase composition, chemical structure of different SwL were evaluated. Finally, based on different combination of SBS and SwL, the effects of SBS/SwL on the microwave absorption in the frequency band from 1 GHz to 18 GHz and exothermic characteristics at 2.45 GHz of the modified asphalt were analyzed. The results show that SwL can be synthesized successfully, and the processing temperature significantly affects the structure of SwL. The SBS/SwL-200 modified asphalt has the best microwave absorption and exothermic properties. When used in self-healing asphalt, it is more advantageous to choose 200 °C as the synthesis temperature of SwL.
研究领域:
材料科学
·
土木工程
·
化学工程
✓ 已验证
DOI
高影响因子
Arabian Journal of Chemistry
·
2023
·
IF 6
Bocong Li,Guoqiang Xiang,Gao Huang,Xiuming Jiang,Lijun He
A rapid, green synthesis strategy assisted by a self-exothermic reaction was designed to prepare highly luminescent carbon dots (CDs) from Ganpu tea infusion (G-CDs) within 5 min using H 2 O 2 and diethylenetriamine (DETA) as the exothermic reactants. G-CDs were successfully obtained through a self-exothermic reaction The prepared G-CDs exhibited clear excitation-dependent characteristics and displayed a strong ultraviolet fluorescence emission (385 nm) at the excitation wavelength of 320 nm. The fluorescence of G-CDs was quantitatively quenched by para -nitrophenol (p-NP) with a concentration range of 0.05–50 µM through inner filter effect (IFE). Since p-NP is one of the hydrolysates of the substrate pNPG under the action of Beta-glucosidase (β-Glu), a new fluorescence assay was developed for the indirect determination of β-Glu activity. The detection limits of G-CDs based fluorescence assays are 14.6 nM for p-NP and 0.074 U·L -1 for β-Glu activity, respectively. The developed fluorescence assays were successfully applied to the detection of p-NP in water and human urine samples and β-Glu activity in fruit samples with satisfactory results.
研究领域:
分析化学
·
生物化学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED THERMAL ENGINEERING
·
2022
·
IF 6.465
Zhigao Sun,Zhifan Chen,Mingrui Liu
In order to improve the thermal conductivity of organic phase change materials and overcome the shortcomings of large supercooling degree and phase separation of inorganic phase change materials, the composites of sodium acetate, stearic acid and octadecyl alcohol as phase change materials were prepared by melt blending method, where disodium hydrogen phosphate dodecahydrate was used as nucleating agent and carboxymethyl cellulose as thickener in this work. XRD, DSC and T-history techniques were used to analyze the composite phase change materials. Sodium acetate, stearic acid and octadecyl alcohol are physically blended in the ternary composite phase change materials. Sodium acetate improves the thermal conductivity and latent heat of the eutectic mixtures of stearic acid and octadecyl alcohol, where the thermal conductivity and latent heat of the eutectic mixtures of stearic acid and octadecyl alcohol is increased by 384 % and 28%, respectively. Heat conduction and natural convection act together, but natural convection plays an important role in the melting process. While heat conduction plays an important part in the discharging process. Due to natural convection, the charging time of the composite phase change materials is less than the discharging time.
研究领域:
材料科学
·
热能工程
✓ 已验证
产品关联
DOI
高影响因子
Defence Technology
·
2020
·
IF 2.637
Yue-ting Wang,Xiao-ting Zhang,Jian-bing Xu,Yun Shen,Cheng-ai Wang,Fu-wei Li,Ze-hua Zhang,Jian Chen,Ying-hua Ye,Rui-qi Shen
In this study, Al–CuO nanocomposites were fabricated by sol-gel method. As a contrast, the thermite was prepared by physical mixing at the equivalence ratio of 0.5, 1, 2, respectively. The intermediates and samples as prepared were characterized by SEM and XRD. The exothermic properties of the two samples prepared at different equivalence ratios were tested and the reaction products were characterized by XRD. The SEM results show that the sample prepared by the sol-gel method demonstrates a micron-sized agglomerated sphere formed by a mutual wrapping of Al NPs and CuO NPs, and the particles are evenly distributed in the agglomerate. In addition, when the content of Al powder is seriously insufficient, the heat release of the sample prepared by physical mixing is 1.6 times that of by sol-gel method. With the increase of Al powder content, the exothermic properties of Al/CuO NPs prepared by sol-gel method began to increase significantly compared with physical mixing and the difference is 1.5 times when the equivalence ratio increases to 2. It can be concluded that the reason for this result may be attributed to the different mass transfer modes of components due to the different morphologies of samples.
研究领域:
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
Energies
·
2024
·Vol. 17
·期 20
·5033
·
IF 3
Yutong Xiao,Siyu Wei,Yuanyi Yang,Chunhao Wang,Shanbi Peng
As a passive solar design technology, the Trombe wall can improve buildings’ energy efficiency and thermal comfort. However, the traditional Trombe wall heating efficiency is low and cannot meet the needs of continuous night heating of the building. To solve these problems, a new type of sheet-like composite adsorbent is proposed in this study, prepared from calcium chloride supported by a rock wool board, a high-porosity building material. The high adaptability of rock wool board to the building wall makes it possible for the composite adsorbent to be directly applied to the Trombe wall. The results show that the macroporous structure of the rock wool board provides a wealth of space for loading hydrated salts. The smaller the density and thickness, the more calcium chloride the rock wool board can carry, speeding up the absorption/deportation process. The rock wool slab-based calcium chloride composite adsorbent has a maximum adsorption capacity of 51% and a heat storage density of about 838 J/g. Achieving the desorbed balance within 8 h and applying it to the Trombe wall is expected to attain continuous heating of buildings and has significant potential in building energy conservation.
研究领域:
建筑材料
·
太阳能技术
·
能源储存
✓ 已验证
产品关联
DOI
高影响因子
Journal of Applied Biomaterials & Functional Materials
·
2020
·
IF 2
Xue Xia,Rui Shi,Jinhui Huang,Yubao Li,Yi Zuo,Jidong Li
The aim of the current study is to alleviate the adverse effect of the strongly exothermic polymerization of polymethyl methacrylate (PMMA) bone cement in clinical applications. In this study, paraffin/poly(methyl methacrylate–methylene bisacrylamide) (paraffin/P(MMA-MBA)) phase change microcapsules (MPn; n = 1, 2) were developed via the emulsion polymerization method. The reduction of the maximum temperature of polymerization (Tmax) and physicochemical properties were evaluated after doping commercial PMMA cement with MPn in specific proportions (10%, 20%, and 30%). The results reveal that the MPn-doped PMMA exhibited an effective reduction in Tmax, which can help alleviate the adverse effect of the strong exothermic reactions during PMMA setting. After doping with the MPn, the mechanical properties of the PMMA cement decrease and the values are close to that of body cancellous bone. The Tmax of the cement doped with 20 wt% MP1 is 37.6°C, which is close to body temperature. Significantly, the setting and compressive properties of the optimized group can still adhere to clinical requirements. The MPn doping PMMA technique holds much promise in clinical practice.
研究领域:
材料科学
·
生物医学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）